When two people really want to be in a relationship, most things can be worked out. However, with ups and downs in relationships, come darker areas, like that of cheating on someone you love, or are in a relationship with.
Can cheating be forgiven? Can it be fixed? Can it be overlooked? Does it mean there's no love left in a relationship? Different couples feel differently.
And, sure, while there can never be a good-enough explanation for something like cheating - after all, it is a betrayal of one's love and trust - some people took to Reddit to elaborate on their reasons for cheating.